Directly setting an object which contains an optional item defined with an interface doesn't bypass Object is possibly 'null' or 'undefined'.

[mckaysalisbury]

TypeScript Version: 3.9.0-dev.20200305

Search Terms:

• object is possibly 'null' or 'undefined'

Code
https://github.com/mckaysalisbury/typescript-direct-set

// See the above repo for a little more self containment.
// Most notably `"strictNullChecks": true`
interface I {
  optional?: (I | null);
  required: number;
}

let workaround: I;
workaround = {
  optional: { required: 2 },
  required: 1
};

workaround.optional.required;  // This is where the error occurs

Expected behavior:
This code should properly compile without errors, even with "strictNullChecks": true
Actual behavior:
With "strictNullChecks": true, there is a possibly undefined error.

Playground Link:
Typescript Playground

Related Issues:

• Object is possibly 'undefined' while strictNullChecks is false? #35523
  Not that related
• Object is possibly null inside a closure defined within a const constraint #36193
• Strange "Object is possibly 'null'" assumption #35964